Swiss Legend Men&#39;s 10127-BKBD Commander Diamond Chronograph Black Ceramic Watch Precise Swiss-quartz movement Scratch-resistant sapphire-crystal; black polished high grade ceramic case and bracelet Chronograph functions with 60 second, 30 minute and 1/10 of a second subdials; date function Black textured dial with luminous hands and 10 full cut white diamond hour markers; screw down crown; unidirectional rotating outer bezel; tachymeter on inner bezel Water resistant to 330 feet (100 M): suitable for snorkeling, as well as swimming, but not diving